Two forward slashes (//, no space between them) indicate that all text following the slashes (until the next carriage return) is a comment. Comments let you provide reference information and notes describing your code:

x = 4 * y // multiply the value of y by four and assign the result to variable x

Two ampersands (&&) can also be used for an end-of-line comment, but they are usually seen in older code.

If an asterisk (*) is the first character in a statement, the entire line is considered a comment.

A pair of single forward slashes with "inside" asterisks (/* */) encloses a block comment that can be used for a multi-line comment block:

/* this is the first line of a comment block

this is more of the comment

this is the last line of the comment block */

You can also use the pair for a comment in the middle of a statement:

x = 1000000 /* a million! */ * y

Comment blocks cannot be nested. This example shows improper usage:

/* this is the first line of a comment block

this is more of the same /* this nested comment will cause problems*/

this is the last line of the comment block */

After the opening block marker, dBASE Plus ends the comment at the next closing block marker it finds, which means that only the section of the comment from "this is the first line" to the word "problems" will be interpreted as a comment. The unenclosed remainder of the block will generate an error.